To determine the molar mass of aluminum chloride AlCl3 , we need to add the molar masses of aluminum Al and chlorine Cl together. The molar mass of aluminum is 26.98 g/mol, and the molar mass of chlorine is 35.45 g/mol. Since there are three chlorine atoms in AlCl3, we need to multiply the molar mass of chlorine by 3.Molar mass of AlCl3 = molar mass of Al + 3 * molar mass of Cl Molar mass of AlCl3 = 26.98 g/mol + 3 * 35.45 g/molMolar mass of AlCl3 = 26.98 g/mol + 106.35 g/molMolar mass of AlCl3 = 133.33 g/molSo, the molar mass of aluminum chloride AlCl3 is 133.33 g/mol.